Piano and the like musical instruments



Aug. 9, 1960 KINYA YAMAMOTO ETAL 2,948,179

PIANO AND THE LIKE MUSICAL INSTRUMENTS Filed June 6, 1956 3 Sheets-Sheet. 1

INVENTORS KM YA YA/7/4 7 60050 /r0/(A M4 BY I 44M 0% M M ATTORNEYS.

1960 KlNYA YAMAMOTO ETAL 2,948,179

PIANO AND THE LIKE MUSICAL INSTRUMENTS Filed June 6, 1956 3 Sheets-Sheet 2 |NVENTOR5- K/lVY/I YAMAMO 7'0 ATTORNEYS Aug. 9, 1960 KINYA YAMAMOTO EI'AL 2,948,179

' PIANO AND THE LIKE MUSICAL INSTRUMENTS Filed June 6, 1956 3 Sheets-Sheet 3 Fig. 4

INVENTORS. K/A YA 7/4/7/4/707' ///0[0 /7 0 (A WA AWQRNEYS.

United States Patent PIANO AND THE LIKE MUSICAL INSTRUMENTS Kinya Yamamoto, Kitatamagun, and Hideo Itokawa, .Setagayaku, Tokyo, Japan, assignors to Masato Yamai,

Tokyo, Japan Filed June 6 1956, Ser. No. 589,703

Claims priority, application Japan Sept. '2, 1955 6 Claims. (Cl. 84-198) The present invention relates to the improvements in pianos and like musical instruments. It is .a device where the interaction between ordinary or primary strings, secondary strings and a sound board can be originated by setting a group or groups of secondary strings, each corresponding to ordinary strings (primary strings), on the back of a sound board behind the ordinary strings.

An object of this invention is to amplify the sound of an instrument as well as to get uniformity of sound volume.

Another object of this invention is to produce a more beautiful tone during performance on a stringed instrument.

A further object is to improve the effect of the secondary strings for high tones by dividing the secondary strings into two groups, one for medium and high tone and another for low tone.

A still further object is to control the excessive residue of resonance on the secondary strings by dampers for the secondary strings.

The combined effect of the invention described above improves the tone of the instruments remarkably so that when applied to an upright piano the sound produced from it is comparable to that of a grand or concert piano.

The figures show an embodiment of this invention on an upright piano.

Fig. 1 is a longitudinal sectional view of the piano having this device.

Fig. 2 is a rear elevational View of the piano showing the elements of this device.

Figs. 3 and 4 are perspective views showing another example of the invention having mechanism for controlling the excessive residue of resonance on secondary wires, Fig. 3 showing a pedal mechanism, and Fig. 4 showing an inside view of the controlling mechanism.

Fig. 5 is a perspective view of the sound board of the piano.

Fig. 6 is a perspective view showing still another example of this invention wherein a curved reflector is provided in the rear of an upright piano.

In Fig. 1 an upper strengthening plank 56 made of metal, veneer or plastic is secured on the soundboard 3 of the upright piano 55, and tuning pins 52 are fitted on the plate.

The new piano is the same as the conventional piano in that piano strings are strung between tuning pins 52 and hitch pins 53 on a lower supporting plank 57, and that the piano strings are stopped by upper and lower bridges 58, 59.

In this invention a group or groups of secondary strings are mounted behind the sound board. In the examples of Fig. l and Fig. 2 a group of vertical secondary strings 22 is fixed between an upper inside supporting plank 6 and a lower inside supporting plank 7 by tuning pins 20 and hitch pins 21 behind the sound board 3. The wires are stopped by an upper bridge 8 and a lower bridge 9.

In the same manner (see Figure 2), keeping a narrow distance between the vertical secondary strings, horizontal 2,948,179 Patented Aug. 9, .1960

fice

secondary strings 23 stopped by bridges 12 and 13 are fixed by tuning pins 0.0 and hitch pins 21' on a right and left inside supporter 10, 11 respectively.

Those horizontal and vertical secondary strings .are stopped by inner bridges. 14 and 15 secured on the sound board.

During performance on this piano, when a key is struck, the vibration of a primary string 50 is transmitted to the middle bridge 51 and then to the sound board 3. This vibration is responded to by either of the two grounds of secondary strings which will amplify the vibration of the sound board cooperating with the primary strings.

For the assembly of this mechanism, steel plates 6, 7, 10, 11 and strengthening steel plates 16, 17, 18, etc., for an upper, lower, right and left bridge are fitted together by bolts and nuts to form a frame, on which the tuning pins 20 and the hitch pins 21 are fixed. After this frame is fixed to the body of the piano, secondary strings 22 of different diameters or proper frequencies are strung vertically between the tuning pins 20 and the hitch pin 21.

The vertical secondary strings 22 have the same interval as the music wires of the chromatic scale, being adjusted from the right to the left as shown in Fig. 2.

The horizontal secondary strings 23 are made of paralleled piano wires with copper wires coiled thereon, each corresponding to one of the music strings for the keys from No. 1 to No. 26. They are adjusted. by tuning pins 21 to repsond to the intervals of music strings, the top corresponding to the No. 1 key and so successively downwardly.

Although in the example of Fig. 2 secondary strings are divided into two groups of vertical and horizontal strings, one for medium and high tone and another for low tone, they, 27 in all, may be set only in the vertical direction with the same 5th mean interval.

The latter arrangement of secondary strings has the effect of increasing the sound volume and refining the tone, but the interaction between the secondary strings for high tone and the primary strings is not as complete when compared with the former arrangement.

In the example of Fig. 2 the secondary strings have tone ranging from the lowest tone corresponding to the No. 1 key up to small 0 on the chromatic scale.

Our careful study on the propagation direction on a sound board proved that meduim and high tone runs along the straight grain of the sound board as shown in Fig. 5 by an arrow 24, and low tone along a rod 4 as indicated by an arrow 25. Considering the above described results the inner bridge was separated into two parts, one for medium and high tone as shown in Fig. 2 at 14 and another for low tone indicated at 15.

Thus, as shown in Fig. 2, a secondary string, corresponding to a primary string for the No. 1 key with a length of 1.15 meters, has the same length of 1.15 meters. The twenty-six strings for low tone have a length ranging from 1.15 to 1.05 meters, but the secondary strings for medium and high tones have the same length of 0.85 meter.

Our experience proves that the volume and the beauty of the sound produced by this new piano is comparable with that by a semi-concert piano.

Since a remarkable increase of sound volume sometimes means an excess residue of resonance, a method for controlling it was devised.

As shown in Figs. 3 and 4 a proper damper is added to this mechanism to work on the secondary strings.

A conventional piano has a lever for forte with a pedal 26 at one end. In this invention another lever 28 for the damper of the secondary strings is connected to this pedal.

When the pedal is pushed down by a foot the movement is transmitted to levers 28, 30, 31 and then to a bellcranlg 31', which in turn moves a shaft 32 towards the soundboard and the damper 33 goes out of contact with the secondary strings. When the foot is removed, by the work of tension springs, the lever mechanism returns to the former position, and the damper 33 pushes against the secondary strings, damping the excess residue of resonance.

Besides this damping mechanism a hand-operated mechanism is fitted to the piano in order to move another damper 35 for medium and high tone through a rod 34. This hand-operated mechanism comprises a heart-shaped cam 36. When the rod 34 contacts with the longer radius 41 of the cam as shown in Fig. 4, the damper 35 is freed from the secondary wires andwiththe shorter radius 40 the damper presses against the secondary strings to damp their excess vibration; g

The use of this damper depends upon the type of music and the cam is set before performance.

The combined effect of the dampers described above minimizes the excess residue of resonance and improves the tone of the piano.

The effect of the sound will be much more improved When the upright piano having this device is fitted with a reflector comprising side boards 39, 39' and a reflecting board 37, as shown in Fig. 3.

As shown in Fig. 6 good results will be obtained from a reflector made of a number of boards united, with a grid of bars 38 secured on it in order to get effective reflection, the area between the bars being narrower from bottom to top.

What is claimed is:

1. In an upright piano having one vertically extending sound board mounted therein; a first set of pins mounted in the forward side of said sound board; a set of conventional strings tensionally carried by said first set of pins; a second set of pins mounted on the rear side of said sound board; a first set of secondary strings tensionally carried by said second set of pins in spaced relationship to said set of conventional strings; said first set of secondary strings being substantially perpendicular to said set of conventional strings; a third set of pins mounted on the rear side of said sound board, and a second set of second- '4 v ary strings tensionally carried by said third set of pins in spaced relationship to said conventional set of strings and said first set of secondary strings; said second set of secondary strings being substantially parallel to said conventional set of strings, whereby said first and second set of secondary strings will respectively vibrate sympathetically when medium and high tones or low tones are emitted from said conventional set of strings.

2. In an upright piano, the device according to claim 1 including first, second and third bridge means disposed respectively between said sound board and said conventional strings; said sound board and said first set of secondary strings and said sound board and said second set of secondary strings.

3. In an upright piano, the device according to claim 1, including a curved reflector mounted therein substantially parallel to said sound board and in spaced relationship thereto. a p

4. In an upright piano, the device according to claim- 2, wherein said first and second bridge means are respec tively substantially perpendicular to said conventional set of strings and said first set of secondary strings, and wherein said third bridge means are mounted at an angle to a plane perpendicular to said second set of secondary strings. a

5. A device as defined in claim 1 wherein said upright piano is provided with a foot pedal and a damper for said conventional strings, and wherein a damper is provided for said first set of secondary strings, linkage interconnecting said dampers whereby they are operable simultaneously upon movement of said foot pedal.

6. A device as defined in claim 1 wherein a hand operated damper is provided for said second set of'secondary strings.

References Cited in the file of this patent UNITED STATES PATENTS t .2-

Clark Dec. 15, 1914 

